a rectangle PQRS inscribed in a quadrant of circle of radius 13cm. find area of rectangle.

Answer 1

Place the circle with centre at (0,0).
So rectangle has vertices at (0,0), (x,0), (x,y) and (0,y)
area = xy
but x^2 +y^2 = 13^2
y = √(169 - x^2)

area = x√(169-x^2)

If you want the MAXIMUM area, you would now differentiate that , set it equal to zero, and solve for x